Jerry Dammers' Spatial AKA Orchestra, Barbican Theatre, London

Economic uncertainty, racial tension, a looming Tory government; not much has changed since the heady summer of 1979, when The Specials (then known as The Special AKA) first bounded out of Coventry.

The band's debut single, "Gangsters" – 169 seconds of ska-punk vitriol aimed at a failing fat-cat establishment that, quite frankly, could have been written about Fred the Shred and his band of bankers – rocketed to number six in the charts, a perfect soundtrack to Britain's growing social unease. Perhaps that's why six former members of The Specials decided to re-form this summer – to cash in on the nation's contemporary discontent.

However, Jerry Dammers' invitation to the party was swiftly revoked after he voiced his intention to rework some of the old classics, meaning that on their 30th-anniversary reunion tour, The Specials will be without the man who wrote most of the songs and hand-picked each band member.

Still, perhaps it's for the best, because while the other members of The Specials have been supping pints at ska and scooter festivals since the bulk of the band's demise in 1981, Jerry Dammers has been experimenting with jazz and afrofuturism.

His Spatial AKA Orchestra (geddit?) were initially formed as a kind of tribute to the cosmic free-jazz pioneer Sun Ra, whose space-themed big-band music fills much of tonight's set.

Coming on stage dressed like Ancient Egyptian wizards, the 18 members that make up the orchestra look like something out of Bill Bailey's darkest nightmare. Among their ranks are Mercury Prize nominees Denys Baptiste and Zoe Rahman, on saxophone and piano respectively, BBC Jazz Award winner Finn Peters on flute, and 1960s free-jazz icon Larry Stabbins, again playing sax.

After a spoken-word introduction from the Trinidadian poet Anthony Joseph, the orchestra erupts into a wonderful, swirling wall of sound. Rather than simply recreate the music of Sun Ra on songs such as "It's after the End of the World", Dammers and his band completely reimagine them.

The wonderfully thick, wet bass lines invoke King Tubby's sound system far more than a smoky Chicago jazz dive while, from behind his giant bank of keyboards, Jerry Dammers unleashes contemporary drum & bass loops to conflict with the frantic horn and woodwind sections.

Tonight is a tribute not just to Sun Ra but also to his peers and influences. Martin Denny's exotic "Jungle Madness" gets a solid turning-out, while Alice Coltrane's dark and pounding "Battle at Armageddon" provides the night's most memorable moment, when Patrick Illingworth performs a truly breathtaking three-minute drum solo.

Part of the justification surrounding Dammers' ban from the Specials reunion includes the fans' belief that he has sold out on his punk credentials. True, in playing a 15-minute-long free-jazz version of the Batman theme, Dammers has entirely broken the golden rule of his generation. But the simple fact that he has dared to do so is considerably more punk rock than the irrelevant nostalgia-fest the rest of The Specials will be laying on this summer. Jerry Dammers as a cosmic free-jazz progressive? How times change.